Internal combustion engine



y 1939- G. E. SANDBLOM 2,160,755

H, INTERNAL COMBUSTION ENGINE Filed May 18, 1938 INVENTOR' GIDEON EFRAIM5A NDBLO/M By I ATTORNEY.

Patented May 30, 1939 UNITED STATES PATENT OFFICE "2480, 355 INTERNALCOMBUSTION ENGINE *Gide'on llfraim Sandblom, Farjenas, near Gothenburg,Sweden 1 Claim.

The present invention relates to internal combustion engines having areciprocating piston and an admission and an exhaust valve arranged atthe top of the working cylinder.

One object of the invention is to provide a combustion engine of thekind referred to in which the compression ratio may be chosen very highwithout any risk of advanced self-ignition.

A further object of the invention is to provide a combustion engine inwhich the fuel and air will be mixed very intimately.

Some embodiments of the invention are shown in the drawing, wherein:

The figure is an axial section through an aircooled single-cylindercombustion engine according to the one embodiment.

Referring to the figure reference numeral l designates the crank case, 2the working cylinder connected to said crank case and 3 the piston whichis by means of the rod 4 connected to the crank 5 of the crank shaft 6.From the upper end of the cylinder there projects laterally a valvechamber 1, with a channel 8 for the supply of fuel-air mixture and achannel 9 for the discharge of the combustion gases. The upper end ofthe cylinder is closed by a cover II) which together with the valvechamber forms a combustion chamber 1 l communicating with the upper endof the cylinder. The combustion chamber ll communicates through anopening controlled by a mushroom valve l2 with the channel 8 for thefuel-air mixture and through another opening controlled by a mushroomvalve I3 with the discharge channel 9. The spindles lZa and Bit of thesevalves are parallel to each other and are operated by the cams l4, l5 oftwo parallel cam shafts I6, I! journalled in a casing 2|, which issupported by a bracket 200 projecting from the crank case I. Each camvshaft carries a toothed wheel l8 and I9 respectively which toothedwheels mesh with each other and are driven from the crank shaft 6 bymeans of a chain 20. As the crank shaft 6 rotates the cam shafts I6, I!will by means of the cams l4, 15 in a usual manner timely open thevalves l2, [3 which are brought back to closed position by the valvesprings I21 I322.

The seat of the admission valve l2 which is located at the inner end ofthe combustion chamber II, is in relation to the seat of the exhaustvalve l3 drawn back in the direction of valve shaft l2a, so as to forman enlarged portion 2| 0 at the inner end of the combustion chamber llto which enlarged portion 2H] the outer, more narrow portion 22 of thecombustion chamber is mainly tangential. The inner enlarged portion 2)of the combustion chamber ll may be of cylindrical, spherical or similarshape. The sur- 5 face of the admission valve I2 facing towards theinterior of the combustion chamber may suitably be concave. Thedischarge valve [3 is located at the outer, narrow portion. 22 of thecombustion chamber l I and the surface of the discharge valve facingtowards the combustion chamber is slightly convex and forms, When saidvalve is in closed. position, together with that portion 23 of thecombustion chamber Wall which is situated between the valves l2, l3 anevenly curved surface. For the ignition of the fuel-air mixture there isprovided a sparking plug H0.

During the suction stroke of the piston the fuel-air mixture enteringthe combustion chamber through the admission valve l2 will with verylittle resistance flow into the cylinder and thereby sweep over thedischarge valve l3 which thus will be thoroughly cooled. During thecompression stroke of the piston the fuel-air mixture is forced backinto the combustion chamber H and L will sweep over its walls which willbe cooled at the same time as the fuel and the air due to the occurringturbulence of the fuel-air mixture willi be intimately mixed.

The scope of the invention is not limited to the embodiment shown anddescribed but may be varied in details without departing from the.spirit thereof.

What I claim is:

In an internal combustion engine having" a 3;; working cylinder anda-reciprocating piston, a combustion chamber communicating at its oneend with the upper end of said working cylinder;, a mushroom valve forthe supply of fuel-air mix-- ture arranged at the inner portion of saidcombustion chamber and provided with a valve spindle, the seat for saidvalve being drawn back in: the direction of said valve spindle so as toform: at the inner end of said chamber an enlarged por tion of saidchamber, a discharge valve for the 45' combustion gases arranged betweensaid admi'se sion valve and said working cylinder, that pore tion of thewalls of said; chamben, which is lo'- cated between the seats of saidvalves forming; together with the outer surface of said discharge 50)valve an evenlyrcurved' surface;v

QIDEQNE EWIM SANDIBLOM;-

